Speech amplifier tube



FIG. 1 is an isometric view of a speech amplifier tube showing my new design, the broken line showing of the human head is for illustrative purposes only and forms no part of the claimed design;

FIG. 2 is an enlarged top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a front elevational view thereof;

FIG. 6 is a left side elevational view thereof; and,

FIG. 7 is a rear elevational view thereof. 

The ornamental design for a speech amplifier tube, as shown and described. 